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With the ever-increasing concern in network security and privacy, a major portion of Internet traffic is encrypted now. Recent research shows that more than 70% of Internet content is transmitted using HyperText Transfer Protocol Secure (HTTPS). However, HTTPS encryption eliminates the advantages of many intermediate services like the caching proxy, which can significantly degrade the performance of web content delivery. We argue that these restrictions lead to the need for other mechanisms to access sites quickly and safely. In this paper, we introduce QoS3, which is a protocol that can overcome such limitations by allowing clients to explicitly and securely re-introduce in-network caching proxies using fine-grained trust delegation without compromising the integrity of the HTTPS content and modifying the format of Transport Layer Security (TLS). In QoS3, we classify web page contents into two types: (1) public contents that are common for all users, which can be stored in the caching proxies, and (2) private contents that are specific for each user. Correspondingly, QoS3 establishes two separate TLS connections between the client and the web server for them. Specifically, for private contents, QoS3 just leverages the original HTTPS protocol to deliver them, without involving any middlebox. For public contents, QoS3 allows clients to delegate trust to specific caching proxy along the path, thereby allowing the clients to use the cached contents in the caching proxy via a delegated HTTPS connection. Meanwhile, to prevent Man-in-the-Middle (MitM) attacks on public contents, QoS3 validates the public contents by employing Document object Model (DoM) object-level checksums, which are delivered through the original HTTPS connection. We implement a prototype of QoS3 and evaluate its performance in our testbed. Experimental results show that QoS3 provides acceleration on page load time ranging between 30% and 64% over traditional HTTPS with negligible overhead. Moreover, QoS3 is deployable since it requires just minor software modifications to the server, client, and the middlebox. [ABSTRACT FROM AUTHOR]

We report a simple strategy to prepare Tween 60@2β-CD self-assembly vesicles in aqueous solution as a new drug delivery carrier for cancer chemotherapy. The spherical shape of vesicles was confirmed by transmission electron microscopy (TEM) and mean particle sizes were about 33.7 nm, as measured by dynamic light scattering, micro-IR results indicated that the self-assembly vesicles was driven by hydrogen bonding. Hydrophilic doxorubicin (DOX) was successfully loaded into the self-assembly vesicles with drug loading content of 7.85% and loading efficiency of 42%. In addition, an in vitro cytotoxicity study and cellular uptake assays demonstrated that the DOX-loaded Tween 60@2β-CD vesicles markedly enhanced the cellular uptake and cytotoxicity of DOX toward the Hela cells. Furthermore, when used to evaluate the in vivo therapeutic efficacy in mice bearing the breast cell line (4T1), DOX-loaded vesicles exhibited superior inhibition of tumor growth compared with the DOX solutions. [ABSTRACT FROM AUTHOR]

The aim of the present study was to develop a novel semi-solid self-microemulsifying drug delivery system (SMEDDS) using Gelucire®44/14 as oil with strong solid character to improve the oral bioavailability of poorly soluble drug valsartan. The solubility of valsartan in various excipients was determined, the pseudo-ternary phase diagram was constructed in order to screen the optimal excipients, and DSC analysis was performed to evaluate the melting point of SMEDDS. The optimal drug-loaded SMEDDS formulation was consisted of 30% Gelucire®44/14 (oil), 40% Solutol®HS 15 (surfactant), and 30% Transcutol®P (cosurfactant) (w/w) with 80 mg valsartan/g excipients. The average droplet sizes of the optimized blank and drug-loaded SMEDDS formulations were 26.20 ± 1.43 and 33.34 ± 2.15 nm, and the melting points of them were 35.6 and 36.8 °C, respectively. Thein vitrodissolution rate of optimal semi-solid SMEDDS was increased compared with commercial capsules, resulting in the 2.72-fold and 2.97-fold enhancement ofCmaxandAUC0–tafter oral administration in rats, respectively. These results indicated that the novel semi-solid SMEDDS formulation could potentially improve the oral bioavailability of valsartan, and the semi-solid SMEDDS was a desirable system than the traditional liquid SMEDDS because it was convenient for preparation, storage and transportation due to semi-solid state at room temperature and melted state at body temperature. [ABSTRACT FROM AUTHOR]

The aim of this study is to elucidate the impact of surface charge of glycerol monooleate-based nanoparticles (NPs) on the cellular uptake and its distribution in the cochlea. These NPs are modified using varied concentration of anionic or cationic lipid. Upon dilution, these lipid mixtures self-assemble to form a series of cubic NPs with various surface charges, but with similar particle size. Positively charged NPs exhibited dose-dependent cytotoxicities against L929 cells proportional to the concentration of cationic lipid; whereas negatively charged NPs did not show obvious cytotoxic properties as compared to unmodified NPs. Meanwhile, confocal microscopy and flow cytometry results suggested that NPs with high positive surface charge were taken up more efficiently by L929 cells. The permeability of round window membrane (RWM) was high for highly positively charged NPs, which is likely due to their highly cellular uptake efficiency and consequently high concentration gradient between RWM and cochlear fluid. More importantly, 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) modified NPs greatly facilitated broadly distribution in cochlea, favoring the treatment of hearing loss of low frequencies. Taken together, these findings about charge-dependent of NPs on RWM permeability and cochlear distribution could serve as guideline in the rational design of NP for drug and gene delivery to inner ear. [ABSTRACT FROM AUTHOR]

The article discusses research on the anisotropic overgrowth of metal heterostructures induced by a site-selective silica coating. It explains the presentation by anisotropic metal nanostructures of morphology-dependent properties. It also offers information on the role of molecular capping in anisotropic growth systems.

The combination of chemotherapy and phototherapy has attracted increasing attention for cancer treatment in recent years. In the current study, porous PdPt bimetallic nanoparticles (NPs) were synthesized and used as delivery carriers for the anti-cancer drug doxorubicin (DOX). DOX@PdPt NPs were modified with thiol functionalized hyaluronic acid (HA-SH) to generate DOX@PdPt@HA NPs with an average size of 105.2 ± 6.7 nm. Characterization and in vivo and in vitro assessment of anti-tumor effects of DOX@PdPt@HA NPs were further performed. The prepared DOX@PdPt@HA NPs presented a high photothermal conversion efficiency of 49.1% under the irradiation of a single 808 nm near-infrared (NIR) laser. Moreover, NIR laser irradiation-induced photothermal effect triggered the release of DOX from DOX@PdPt@HA NPs. The combined chemo-photothermal treatment of NIR-irradiated DOX@PdPt@HA NPs exerted a stronger inhibitory effect on cell viability than that of DOX or NIR-irradiated PdPt@HA NPs in mouse mammary carcinoma 4T1 cells in vitro. Further, the in vivo combination therapy, which used NIR-irradiated DOX@PdPt@HA NPs in a mouse tumor model established by subcutaneous inoculation of 4T1 cells, was demonstrated to achieve a remarkable tumor-growth inhibition in comparison with chemotherapy or photothermal therapy alone. Results of immunohistochemical staining for caspase-3 and Ki-67 indicated the increased apoptosis and decreased proliferation of tumor cells contributed to the anti-tumor effect of chemo-photothermal treatment. In addition, DOX@PdPt@HA NPs induced negligible toxicity in vivo. Hence, the developed nanoplatform demonstrates great potential for applications in photothermal therapy, drug delivery and controlled release. [ABSTRACT FROM AUTHOR]

[Display omitted] As a new type of antitumor strategy, the combined application of photodynamic therapy and immunotherapy will be a breakthrough in the field of tumor therapy. In this study, PD-L1McAb&HMME@Clip is used as the carrier to improve the low tumor response rate of immune checkpoint inhibitors. Firstly, by passive targeting technology, the carrier is delivered to the tumor site to increase the local drug concentration. Then, by photodynamic technology, HMME can produce large amount of reactive oxygen species and directly kill the tumor cells. Meanwhile, the tumor cell lysate with strong immunogenicity can promote the phagocytosis of dendritic cells and the activation of initial T cells. Finally, by immune technology, the PD-1/PD-L1 pathway is blocked in the tumor microenvironment, the killing ability of T cells to tumor cells can be restored, and the tumor recurrence and metastasis can be effectively inhibited by the autoimmune system, so as to achieve the goal of tumor treatment. Furthermore, we also highlight the potential benefits of immunotherapy as a surgical adjuvant therapy. [ABSTRACT FROM AUTHOR]

This work initially illustrated the formation mechanism of chiral mesoporous silica (CMS) in a brand new insight named biomimetic synthesis. Three kinds of biomimetic synthesized CMS (B-CMS, including B-CMS1, B-CMS2 and B-CMS3) were prepared using different pH or stirring rate condition, and their characteristics were tested with transmission electron microscope and small angle X-ray diffraction. The model drug indomethacin was loaded into B-CMS and drug loading content was measured using ultraviolet spectroscopy. The result suggested that pH condition influenced energetics of self-assembly process, mainly packing energetics of the surfactant, while stirring rate was the more dominant factor to determine particle length. In application, indomethacin loading content was measured to be 35.3%, 34.8% and 35.1% for indomethacin loaded B-CMS1, indomethacin loaded B-CMS2 and indomethacin loaded B-CMS3. After loading indomethacin into B-CMS carriers, surface area, pore volume and pore diameter of B-CMS carriers were reduced. B-CMS converted crystalline state of indomethacin to amorphous state, leading to the improved indomethacin dissolution. B-CMS1 controlled drug release without burst-release, while B-CMS2 and B-CMS3 released indomethacin faster than B-CMS1, demonstrating that the particle length, the ordered lever of multiple helixes, the curvature degree of helical channels and pore diameter greatly contributed to the release behavior of indomethacin loaded B-CMS. [ABSTRACT FROM AUTHOR]

The combination of noble metal and oxide support is a good approach to reduce the cost of noble metal catalyst and improve the stability of nanocatalyst in chemical reactions. Here, noble metal/zinc oxide composites, including Pd/ZnO and Pt/ZnO, have been facilely prepared through the general one-pot hydrothermal method. Importantly, the morphology of composites can be tuned from tube, flower, and star to skin needling-like shapes by easily adjusting the alkalinity of the reaction solution. By investigating the growth mechanism and influencing factors of the morphology of noble metal/zinc oxide composites, the differences of the morphology of composites can be ascribed to various growing units and directions of ZnO crystal under different alkalinities. Among them, Pd/ZnO composites exhibited both higher catalytic activity and excellent stability in the Suzuki coupling reaction between iodobenzene and phenylboronic acid and the reduction of 4-nitrophenol to 4-aminophenol by sodium borohydride. Such supported composites will potentially be used as green and sustainable catalysts for many chemical reactions.

Catalytic microspheres: A general approach is demonstrated for the facile preparation of mesoporous metal oxide microspheres loaded with noble metal nanoparticles (see TEM image in the picture). Among 18 oxide/noble metal catalysts, TiO(2)/0.1 mol % Pd microspheres showed the highest turnover frequency in NaBH(4) reduction of 4-nitrophenol (see picture)., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The formation of different Au nanocrystal core-resin shell structures through the control of the nanocrystal assembly and shell polymerization is investigated. 4-Mercaptophenol is employed together with formaldehyde as the resin monomers. 4-Mercaptophenol molecules bond to the surface of Au nanocrystals so that the resultant phenolic resin can intimately encapsulate Au nanocrystals. The morphologies of the obtained structures are determined by the nanocrystal assembly and the monomer polymerization behaviors, which are controlled by the solution pH as well as the monomer amounts. At pH = 8-9, Au nanorods are assembled and fused together under hydrothermal conditions in a preferential end-to-end manner. The fused structures are coated with a layer of resin, with the thickness controlled by the supplied amounts of the monomers. At pH = ∼10, Au nanorods are coated with resin of controllable thicknesses and separated from each other. The resin-coated Au nanorods are stable in both aqueous and nonaqueous solutions. At pH = ∼12, Au nanorods are coated with a thin layer of resin and assembled together in a side-by-side manner. A similar assembly and resin coating behavior is also observed with Au nanopolyhedrons. Moreover, plasmonic-fluorescent bifunctional structures are readily produced by incorporating CdTe nanocrystals in the resin shell that is coated on Au nanocrystals, owing to the presence of a number of thiol groups in the resin shell.

Bifunctional heterostructures composed of gold nanorods and hematite nanoparticle aggregates are prepared facilely through the hydrothermal decomposition of ferric acetylacetonate on the surface of the nanorods. The gold nanorod in the heterostructure is partially coated with the hematite nanoparticle aggregates. The hematite coating is porous. These heterostructures exhibit both plasmonic and superparamagnetic properties. They are well-dispersed in aqueous solutions. Such heterostructures will be potentially useful for many biotechnological applications., (© 2011 American Chemical Society)

Core-shell Au nanorod-AgAuS nanostructures were hydrothermally prepared from Au nanorods and metal thiobenzoates and then transformed into Au nanoparticle-decorated sulfide nanostructures.

A series of photochromic spirooxazine-containing zinc(II) diimine bis-thiolate complexes were successfully synthesized, and their photophysical and photochromic properties were studied. The X-ray crystal structure of complex 1a has also been determined. Upon excitation by UV light at 330 nm, all the ligands and complexes exhibit photochromic behavior. The thermal bleaching kinetics of the ligands and the complexes were studied in dimethylformamide at various temperatures. The photochemical quantum yields for the photochromic reactions of the ligands and complexes were also determined.